<!--优化：减少label嵌套，去除内层label-->
<label #labelRef class="ti3-checkbox" [for]="id" [id]="appendId('checkbox')">
  <!-- 兼容IE11添加spacebar事件 -->
  <span
    #proxyRef
    class="ti3-checkbox-skin ti3-icon ti3-icon-checkmark"
    tiOutline
    (keydown.spacebar)="onSpaceKeydown($event)"
    (keyup.spacebar)="onSpaceKeyup($event)"
    (keydown.space)="onSpaceKeydown($event)"
    (keyup.space)="onSpaceKeyup($event)"
  ></span>
  <span class="ti3-checkbox-label" [id]="appendId('label')">{{label}}</span>
</label>
